Wrongful Termination?

Out of the blue, my husband was so called layed off from his job on 6/21. On tuesday, we receive a letter from his employer of when his benefits will end. This letter also states that he was layed off or a RIF action is taken due to his postion is eliminated. I am still lost on this action because his work hours for the a few months now have been between 8-12 hours a day and working weekends. We were told by a former coworker that his previous employer is trying to fill the postion with a temp. Could this be a legimate suit against the employer? His former boss could not gave a reason what so ever for the lay off.